The present disclosure relates to graphical digital images. Graphical images can be represented electronically in several types of formats. One type of format is a bitmap image, which is also known as a raster image. A bitmap, or raster, image is typically structured as a grid or array of pixels. For each pixel, a bitmap image includes data to indicate one or more visual properties of that pixel such as color, brightness, hue, transparency, etc.
There are various file formats for electronically storing a bitmap image, namely, Graphics Interchange Format (GIF), Portable Network Graphics (PNG), Tagged Image File Format (TIFF), and Joint Photographic Experts Group (JPEG), among others. Image quality of a bitmap image can correspond to a total number of pixels stored within a given image file, or to a degree of lost data from image compression. As pixel count and quality increases, however, so does a file storage size. Individual bitmap files, and collections of bitmap files, can require large amounts of computer storage.